Data Banks have been developed in Stroke and Traumatic Coma. Organizing the principles for establishing a data bank which describes a neurologic condition requires proposing and testing new concepts of data management. This project has analyzed the underlying organizational and methodological principals which are necessary for optimal functioning of a data bank, has developed a data bank model, and will disseminate information regarding this model. The methodology employed by the data banks includes innovative techniques, such as interactive, on-site data entry, and local edit checking of data. Since the data banks consist of multiple clinical centers, which collaborate and pool data, stringent techniques are required to ensure consistent data collection. A data base management system is necessary to handle the hundreds of question parameters involved. Information on this methodology is being disseminated by presentations at seminars, papers, meetings and conferences. A Stroke Data Bank Workshop will be sponsored at the stroke Council of the American Heart Association in 1986. In addition, consultation with other Institutes and with academic medical centers on data bank methodology for chronic disease continues. For example, the Arthritis Institute has implemented a data bank on liver transplants based on the organizational and data management principles of the Stroke and Coma Data Banks.